Vacuum-insulated flask



FIG. 1 is a perspective view of my new vacuum-insulated flask;

FIG. 2 is a front view thereof, a rear view being identical thereto;

FIG. 3 is a right side view thereof, a left side view being identical thereto;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof. 

CLAIM The ornamental design for a vacuum-insulated flask, as shown and described. 